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Reactor Physics Studies For The Afci Reactor-Accelerator Coupling Experiments (Race) Project, Denis Beller

Transmutation Sciences Physics (TRP)

The specific research objective of this three-year project is to design and conduct an accelerator driven experiment at one of the Texas universities. This experiment will help demonstrate in the U.S. the ability to design, compute, and conduct ADSS experiments; and to predict and measure source importance, coupling efficiency, sub-critical reactor kinetics and source-driven transients. In addition, both steady state and transient ADSS benchmarks will be created for the nuclear community to develop and test new computational codes and methods, and the importance of a driving neutron source in various regions of different subcritical assemblies will be mapped. Experiments will …

Development Of A Systems Engineering Model Of The Chemical Separations Process, Yitung Chen, Darrell Pepper, Sean Hsieh

Separations Campaign (TRP)

The chemical processing of used nuclear fuel is an integral component of any strategy for the transmutation of nuclear waste. Due to the large volume of material that must be handled in this first step of the transmutation process, the efficiency of the separations process is a key factor in the potential economic viability of transmutation strategies. The ability to optimize the chemical separation systems is vital to ensure the feasibility of the transmutation program.

Systems analysis, or total systems modeling, is one of the strongest tools available to researchers for understanding and optimizing complex systems such as chemical separations …

Nuclear Criticality, Shielding, And Thermal Analyses Of Separations Processes For The Transmutation Fuel Cycle, William Culbreth, Denis Beller

Separations Campaign (TRP)

The first step in any transmutation strategy is the separation of radionuclides in used nuclear fuel. The current separation strategy supporting the Advanced Fuel Cycle Initiative (AFCI) program is based on the use of a solvent extraction separation process to separate the actinides, fission products, and uranium from used commercial nuclear fuel, and on the use of pyrochemical separation technologies to process used transmuter fuels. To separate the fission products and transuranic elements from the uranium in used fuel, the national program is developing a new solvent extraction process, the Uranium Extraction Plus, or UREX+, process based on the traditional …

Immobilization Of Fission Iodine By Reaction With A Fullerene Containing Carbon Compound And Insoluble Natural Matrix, Spencer M. Steinberg, Gary Cerefice, David W. Emerson

Separations Campaign (TRP)

The recovery of iodine released during the processing of used nuclear fuel poses a significant challenge to the transmutation of nuclear waste. Iodine-129, a long-lived fission product formed by both commercial nuclear power generation and nuclear weapons production, is released when reprocessing nuclear fuel. Since iodine can be concentrated in the human thyroid, any uncontrolled release of iodine may result in an increased rate of thyroid cancer in the exposed population. For this reason, recovery of iodine is important for implementing any nuclear transmutation strategy.

The stability of the association of iodine with FCC and NOM products are studied. Product …

Development, Fabrication And Study Of Fullerene-Containing Carbon Material (Fcc) For Immobilization Of Iodine: Progress Report #1-4, Michael Savopulo, Boris E. Burakov

Separations Campaign (TRP)

During current reporting period the experiments on synthesis of ceramic-like material by conversion of iodine-doped FCC and activated carbon to Si_xC_y have been completed. Cold pressed granules of FCC and activated carbon were rinsed in water-ethanol solution of tetraethoxysilane (TEOS), Si(OC₂H₅)₄, and then used for further synthesis. All new samples obtained have been studied using precise powder XRD analysis.

Development, Fabrication And Study Of Fullerene-Containing Carbon Material (Fcc) For Immobilization Of Iodine: Final Report 2005, Michael Savopulo, Boris E. Burakov

Separations Campaign (TRP)

Immobilization of highly radioactive and long-lived isotope of ¹²⁹I, which is a fission product in spent nuclear fuel, requires development of new durable host-materials.

Iodine is a very volatile chemical element, and even its chemically strong compounds such as AgI and CuI are not stable under ultraviolet irradiation or oxidizing conditions. Therefore, development of host materials for iodine immobilization is based on unusual approach – the search and testing of new compounds which were not studied before in respect of iodine sorption and strong fixation.

Although FCC material demonstrated high loading capacity to iodine sorption it is necessary to …

Evaluation Of Fluorapatite As A Waste-Form Material, Dennis W. Lindle, Oliver Hemmers, Dale L. Perry

Separations Campaign (TRP)

Argonne National Laboratory has proposed a new extraction procedure to handle TRISO-coated fuels, the Fluoride Extraction Process, or FLEX. The FLEX process is designed to separate the uranium in the fuel from the actinides and most fission products by taking advantage of the unique properties of uranium hexafluoride (UF₆). In the FLEX process, the used TRISO fuel is reacted with zirconium fluoride salt, forming UF₆ and the fluoride salts of the actinides and fission products. At process temperatures, the UF₆ volatizes into a gas, and is released from the molten salt mixture. This leaves behind the …

Development Of Fluorapatite As A Waste Form: Final Report #280204-1, Boris E. Burakov

Separations Campaign (TRP)

In the framework of Agreement #280204 (first year) it was necessary to review methods of apatite synthesis; identify optimal procedure of precursor preparation; obtain and study first fluorapatite samples. Although, some apatite-based ceramics were successfully synthesized using co-precipitated precursors and sintering method, there are still a lot of uncertainties related to optimal apatite doping with different radionuclides and non-radioactive elements. It is necessary to provide complete incorporation of waste elements into apatite crystalline structure avoiding formation of separate phases of radionuclides. Also, it is important to note that real waste streams might contain radionuclides with essentially different chemical features such …

Development Of Integrated Process Simulation System Model For Spent Fuel Treatment Facility (Sftf) Design, Yitung Chen, Sean Hsieh

Separations Campaign (TRP)

The major objective is to create a framework that combines all the strengths of AMUSE’s complicated calculations, well established commercial system process package such as ASPENPLUS, HYSYS and PRO/II and TRPSEMPro’s flexible parameter optimization modules. Development of the process simulation code can be done using the solvent extraction process experience at Argonne National Laboratory and in collaboration with the NCACM.

The major activities of the task are the following:

• Develop a framework for simulating the SFTF process using AMUSE code, commercial process package, such as ASPEN- PLUS, and system engineering model.
• Develop a middleware package that can communicate between the …

Electrochemical Separation Of Curium And Americium, David W. Hatchett, Kenneth Czerwinski

Separations Campaign (TRP)

The objective of this project is to use electrochemical techniques to develop a thermodynamic understanding of actinide and lanthanide species in aqueous solution and use this data to effectively separate species with very similar chemical properties. In consultation with our DOE collaborator, electrochemical methods and materials will be evaluated and used to exploit the thermodynamic differences between similar chemical species enhancing our ability to selectively target and sequester individual species from mixtures.

The following were specific goals for this year:

• To develop a fundamental understanding of the thermodynamic properties of actinide and lanthanide species such as Cm, Am, Ce, Nd, …

Fundamental Chemistry Of U And Pu In The Tbp-Dodecane-Nitric Acid System: Quarterly Report, Kenneth Czerwinski, Cynthia-May Gong, Amber Wright

Separations Campaign (TRP)

The speciation of hexavalent U and tetravalent Pu will be examined in the TBPdodecane- nitric acid systems. This topic is chosen based on data needs for separation modeling identified by the AFCI. Emphasis will be placed on studying the influence of nitrate and acetohydroxamic acid on U and Pu speciation as well as conditions where a third phase forms in the organic phase. The organic phase will be 30 % TBP in dodecane. Equal volumes of aqueous and organic phase will be used. The speciation of the actinides in the aqueous and organic phase will be determined by a number …

Fundamental Chemistry Of U And Pu In The Tbp-Dodecane-Nitric Acid System, Kenneth Czerwinski, Byron Bennett

Separations Campaign (TRP)

The research objectives of this project are as follows:

• To determine the influence of nitrate on the speciation of U and Pu in the TBP-dodecane-nitric acid system. The aqueous and organic speciation of U and Pu are examined as a function of the nitric acid concentration, nitrate concentration (by the addition of NaNO₃), actinide ion concentration, temperature, and time.
• To determine the speciation of U and Pu with AHA in the presence and absence of TBP-dodecane organic phase. The aqueous and organic speciation of U and Pu are evaluated as a function of AHA concentration, metal ion concentration, …

Inside Unlv, Erin O'Donnell

Inside UNLV

No abstract provided.

Design Of Fuzzy Logic Based Adaptive Traffic Signal Controller, Murali Mohan Ande

UNLV Retrospective Theses & Dissertations

Traffic control of street intersections is one of the most critical elements in providing an efficient flow of traffic in urban networks. Conventionally, pretimed controllers are used, but they cannot respond to real time fluctuations in traffic demand. Traffic actuated signals provide an improvement over pretimed controllers, but their performance deteriorates under heavy traffic conditions. These conditions necessitate the development of a controller that responds to actual traffic demand in real time, with the objective of minimizing vehicle delays, number of stops, etc. Fuzzy logic provides the potential for development of a system that would address these needs; The objective …

Hydrostratigraphy And Allostratigraphy Of The Cenozoic Alluvium In The Northwestern Part Of Las Vegas Valley, Clark County, Nevada, David Joseph Donovan

UNLV Retrospective Theses & Dissertations

This investigation was conducted to determine the location, nature, and boundaries of the most permeable unit within the alluvial aquifer material in Las Vegas Valley. It was prompted by declines in specific capacity of about 90% at the Las Vegas Valley Water District's West Central Well Field. It was hypothesized that the decline in specific capacity resulted from dewatering of the most permeable interval of the alluvium. Lithologic descriptions from wells and aquifer test information were analyzed for geologic and hydrogeologic variability. New information, in the form of detailed unpublished lithologic and hydrologic information, was available from twenty water wells …

Development Of A Dynamic Spatial Data Analysis System For Transportation, Mukunda Rao Dangeti

UNLV Retrospective Theses & Dissertations

Transportation systems are complex entities that are owned and operated by a diverse group of organizations. The management of such systems requires substantial amounts of data to be monitored, acquired, managed, analyzed, maintained and modeled. Due to the spatial and temporal nature of such data, Geographic Information Systems (GIS) and Global Positioning Systems (GPS) technologies offer significant promise to help with such activities. The focus of this dissertation is to develop a GIS based decision support system to help manage transportation systems. The purpose of the study is to develop a system, which compiles, pre-processes, and manages various transportation system …

Confidence Intervals For The Ratio Of Poisson Parameters, Libo Zhou

UNLV Retrospective Theses & Dissertations

Let k1, k2 be non-negative integers with k1 + k 2 ≥ 2; let X1, X 2,.. Xk1 ;Y1, Y2,.. Yk2 be mutually independent Poisson random variables with parameters lambda 1,lambda2,.. lk1 ; mu1, mu2,.. mk2 , respectively. In this article, we consider constructing confidence intervals for ratio of Poisson parameters q=l1˙l2 ˙l3&cdots;lk1 m1˙m2˙m 3&cdots;mk2 . For the ratio of two Poisson parameters q=l1m1 , an exact formula for confidence interval is given. A numerical method to obtain confidence interval for q=l1˙l2 ˙l3&cdots;lk1 m1˙m2˙m 3&cdots;mk2 is developed. Examples are given for each of the two cases.

Sequential Procedure For Test Of Uniformity In Multinomial Models, Hai Zhen

UNLV Retrospective Theses & Dissertations

In this thesis we deal with a sequential procedure for testing uniformity in a given multinomial distribution using inverse sampling. From a decision theoretic point of view, we devise an efficient stopping rule that satisfies a pre-determined P*-condition. Dirichlet distribution Type II will be primarily used for developing the inverse-type sequential procedure based on the decision theoretic point of view. We assume a non-zero cell probability (parameter) for given multinomial models. In particular, we will be focusing on the equal cell probability configuration (EPC) among all feasible cell configurations. One of the main goals is to find optimal sample sizes …

Confidence Interval Estimation For A Geometric Distribution, Majgan Beria

UNLV Retrospective Theses & Dissertations

A geometric random variable models the number of trials required to obtain the fist success in a Bernoulli process. This distribution has been used by Merrill (2005) as a probability model for the distribution of drivers yielding to pedestrians in a traffic microsimulation investigation. The sample proportion of yielding drivers was calculated using the method of moments, and the bootstrap method was used for computing a confidence interval (CI) for the success probability. The properties of this CI for the geometric distribution, however, have not been investigated. The main objective of this thesis is to develop the performance of the …

Analyzing Association Rules Produced By Applying The Apriori Algorithm To Structured Data, Darshana Gala

UNLV Retrospective Theses & Dissertations

In this thesis, we will use various techniques from data mining to draw interesting results from a set of structured data on personal privacy information. In particular, the well-known, Apriori Algorithm will be used to find frequent item sets and association rules in this data. This process has been shown to be effective in predicting the presence of one type of data when other data is present in other data mining applications; The thesis will also include a detailed analysis of rules generated by the algorithm and their natural interpretations.

Evaluating Hydraulic Conductivity Of Desert Soils At The Amargosa Desert Research Site Near Beatty, Nevada, Jon Woodrow Wilson

UNLV Retrospective Theses & Dissertations

This study tested predictive equations of unsaturated hydraulic conductivity. Quarterly measurements of water-content measured over 12 years were collected from six sites at the Amargosa Desert Research Site (ADRS) located within northern Amargosa Desert, Nevada. ADRS Soils consist of unconsolidated to weakly indurated deposits of early Pliocene and Quaternary age alluvial-fans; fluvial and freshwater deposits; Descriptive statistics and soil properties provide input for method evaluation. Methods include those by Green and Corey (1971), and van Genuchten (1980). Resulting graphical comparisons, for both methods, suggests a good and poor correlation in trench and native devegetated sites, respectively. Conductivity values differing by …

Training Professionals' Impressions And Opinions About Their Role In Hospitality, Valentini Kalargyrou

UNLV Retrospective Theses & Dissertations

Billions of dollars are spent yearly on employee training. Thus, extensive research has been done on why training is important to the advancement of organizations. However, little research has been done on the actual providers and facilitators of the training and development. This research is designed to identify the feelings, insights, emotions, expectations, and beliefs of the training professionals about their role in hospitality. A qualitative research, Zaltman's Metaphor Elicitation Technique (ZMET) was performed with ten training professionals from two hotels in Las Vegas, Nevada. Study results indicated (1) the importance of their role within the organization, (2) the high …

Bayesian Estimation Of The Normal Mean In The Presence Of Non-Detects, Ahmed Khago

UNLV Retrospective Theses & Dissertations

This paper is concerned with the Bayesian approach to estimate the mean when encountered with left-censored data sets. Considering the joint non-informative prior, we derived the posterior probability density function of the mean of left-censored data. However, this density function is not recognizable and we can not analytically integrate it to obtain the normalizing constant. In other words, we can not compute analytically the posterior pdf or posterior moments. Numerical integration involving the adaptive Simpson quadrature rule was used in Mat-lab to obtain the posterior mean and the upper credible limit (UCL). Several numerical examples are given which illustrate the …

Process Analysis And Simulation Of Solar Thermochemical Hydrogen Generation, Mohammad Arif Khan

UNLV Retrospective Theses & Dissertations

In this study three different kind of solar thermochemical cycles (methane reforming process, sulfur-iodine cycle and copper-chlorine cycle) have been analyzed to produce hydrogen gas. Methane reforming processes (steam methane reforming, partial oxidation and autothermal reforming) have been analyzed and simulation flowsheets have been developed. In this analysis, the temperature of all the reforming reactors are varied in the range of 500-1000 °C due to the transient nature of the solar energy. The results show that the POX reforming system is better than the other two systems for the production of the same amount of hydrogen from CH4; Process analysis …

Synthesizing A Piccolo Using Physical Modeling Techniques, Pamela Pnina Mandelbaum

UNLV Retrospective Theses & Dissertations

Physical modeling is a very affective technique used to simulate a musical instrument. It is different than most synthesizing techniques, because the synthesized sound is completely computer generated. It works by starting with a pure frequency and then applying a physical model to this signal. The physical model is created by analyzing the effects that the real instrument would have on a pure signal and then designing a model to simulate these effects using signal processing techniques; The piccolo is an instrument similar to the flute. Music synthesizers will use synthesized flute sounds for music that requires a synthesized piccolo. …

Vissim Model Development Of A Mid-Block Pedestrian Crossing Between Signalized Intersections, John Christopher Merrill

UNLV Retrospective Theses & Dissertations

Pedestrian mid-block crossings through arterial roadways have significant impacts on vehicular level of service and safety. Past research has been conducted to simulate these crossings. However, a practical, realistic model and methodology have not been established for analysis and planning of mid-block pedestrian crossings. The objective of this study was to create a practical traffic microsimulation methodology for mid-block pedestrian crossings through a case study using a versatile transportation software package. VISSIM v3.70 was selected because of its ability to model individual vehicle and pedestrian interactions. The developed methodology provided a framework for model development at any pedestrian mid-block crossing …

Handwritten Number Recognition, Meenakshisundaram Murugan

UNLV Retrospective Theses & Dissertations

The main focus of this research is to automate medical form processing. An important step in this process is separating handwriting from printed text characters. We developed a filtering technique that extracts handwritten text from the printed text in the form. Once the handwritten text is segregated, each line of the segregated text is identified. The identification step is followed by character segmentation. Statistical analysis is performed on the gaps between the characters in each line. This results in a binormal curve clearly depicting two regions indicating if the gap represents the spacing between characters within a word or between …

Conjugacy Numbers For Cyclic Groups Of Even Order, Tanya Jessica Murray

UNLV Retrospective Theses & Dissertations

Let Gamma be a finite group, let X be a subset of Gamma where X-1 = X and 1 ∉ X. The conjugacy graph Con(Gamma; X) has vertex set Gamma and two vertices g, h ∈ Gamma are adjacent if and only if there exists x ∈ X with g = xhx-1. Let O be a group with generating set Delta. The conjugacy number con(O; Delta) is defined as the minimum integer k ≥ 2 for which there exists a nonabelian group Gamma of order k|O| and a subset X of Gamma such that Cay(O; Delta) is isomorphic to a …

Joint Design For Shock Mitigation, Gopi Nallani

UNLV Retrospective Theses & Dissertations

Smart projectiles carry various electronic components that can be damaged by severe shock loads. Propagation of shock from the region of initial loading to the locations of critical components can result in their failure. The objective of the research is to mitigate (absorb/reflect/disrupt, etc.) the incident shock loading, including simulating set-back, set-forward and balloting loads on a projectile as it exits the gun muzzle and predicting the structural response of internal electronic components. A detailed finite element analysis of the projectile and internal components is presented. The effect of electronic component mounting location on peak acceleration and RMS acceleration has …

Policy Analysis: Evaluating Theories Of The Hermeneutic Critique, Cecilea Mun

UNLV Retrospective Theses & Dissertations

This thesis evaluates three theories representing the three perspectives identified by Goktug Morcol as perspectives of the hermeneutic critique in policy analysis, while explicating the revolutionary process that the science is currently undergoing. The evaluation is focused around the question as to whether the three theories are viable alternatives to positivist theories. First, a brief history of policy analysis is presented, highlighting the conditions that contributed to the rise of the general positivist paradigm as the ideal in policy analysis. This is followed by a summary and criticisms of the general positivist paradigm. Next, summaries of Dvora Yanow's interpretive theory, …